Hi
IMHO it is somewhat complex.
The first wargaming miniatures were metallic 30-25 mm , and when the metal prices grown up in the 70-80's, transformed into 15 mm. In those times, most of the 1/72 figures were plastic (do you remember Airfix?) and miniature wargamers, in general, dislike non-metallic figures, so our scale, placed in the middle, was forgotten.
Today there is a change, as some 'big' figure designers (Perry, Victrix...) have started to manufacture hard plastic figures. But again not in 1/72 scale, but in 25-28 mm, so the 'problem' will continue in the future.
Only if there were a sufficient numbers of manufacturers making 1/72 metal figures, our scale would be popular.
However I am very satisfied with my choice.
1/72 for ever !